Skip to content

Relevance & Boosting

When to Use

When tuning search result relevance — making the most relevant results appear first.

Decision: Boost Mechanisms

Mechanism Where Effect
Field boost Index → Fields tab Per-field weight multiplier
HTML element boost HTML Filter processor settings Boost by H1, H2, H3, strong, em tags
Type boost Type Boost processor Boost entire entity types/bundles
Number field boost Number Field Boost processor Boost by a numeric field value
Views sort Views sort criteria Sort by "Search: Relevance"

Pattern: Field Boost Configuration

Set in the index Fields tab — each fulltext field has a "Boost" value: - 1.0 = normal weight (default) - 2.0 = double weight - 0.5 = half weight - 21.0 = maximum (for title fields)

Pattern: HTML Filter Element Boosts

In the HTML Filter processor settings: | Element | Recommended Boost | Rationale | |---|---|---| | H1 | 5 | Page title (if in rendered HTML) | | H2 | 3 | Section headings | | H3 | 2 | Sub-headings | | Strong / B | 2 | Emphasized text | | Em / I | 1.5 | Italicized text |

Pattern: Rendered HTML vs Individual Fields

If using both a Rendered HTML Output field AND individual fields (title, body): - Set Rendered HTML boost to 0.5 or lower - Set Title boost to 13-21x - This prevents the rendered output from diluting the title boost

Decision: Views Sort

Always sort by "Search: Relevance" descending for search results. Views does NOT default to relevance sort — you must add it explicitly.

Common Mistakes

  • Not sorting by relevance — Default Views sort is not relevance. Without it, results appear in arbitrary order.
  • Over-boosting one field — A title at 21x with body at 1x means a partial title match outweighs a perfect body match. Balance boosts.
  • Ignoring HTML filter — The HTML filter processor can boost by element tags inside the rendered HTML, giving heading text more weight without separate fields.

See Also